Ages for Cobaltite at Middlesex Co., Massachusetts, USA

The cyan highlights indicate which age entries were selected as the "best" for assigning the mineral an age of 641Ma - 275Ma at this locality

• Locality age

• Excel ID	Max Age (Ma)	Min Age (Ma)	Dated Mineral	Minerals explicitely stated as having this age	Age applies to these Elements	Dated Locality ID	Dated Locality	Ref	Ref ID
  Alexandra-0416	305	275				22413	Stoneham, Middlesex Co., Massachusetts, USA	Zartman et al. (1970)	GSAB81_3359
  USGS-Rb-Sr-01137	460	460				195966	Burlington, Middlesex Co., Massachusetts, USA	USGS-Rb-Sr	USGS-Rb-Sr
  USGS-Rb-Sr-03298	427.32	285.32				220591	Snake Meadow Hill, Westford, Middlesex Co., Massachusetts, USA	USGS-Rb-Sr	USGS-Rb-Sr
  USGS-Rb-Sr-03299	427.32	285.32				220591	Snake Meadow Hill, Westford, Middlesex Co., Massachusetts, USA	USGS-Rb-Sr	USGS-Rb-Sr
  USGS-Rb-Sr-06235	641	541				212086	Fletcher Quarry (Milford Pink Quarry), Hopkinton, Middlesex Co., Massachusetts, USA	USGS-Rb-Sr	USGS-Rb-Sr
  USGS-U-Th-Pb-01334_206_238	531	521	Zircon			212086	Fletcher Quarry (Milford Pink Quarry), Hopkinton, Middlesex Co., Massachusetts, USA	USGS-U-Th-Pb	USGS-U-Th-Pb
  USGS-U-Th-Pb-01334_207_206	624	614	Zircon			212086	Fletcher Quarry (Milford Pink Quarry), Hopkinton, Middlesex Co., Massachusetts, USA	USGS-U-Th-Pb	USGS-U-Th-Pb
  USGS-U-Th-Pb-01334_207_235	550	538	Zircon			212086	Fletcher Quarry (Milford Pink Quarry), Hopkinton, Middlesex Co., Massachusetts, USA	USGS-U-Th-Pb	USGS-U-Th-Pb
  USGS-U-Th-Pb-01362_206_238	360	352	Zircon			220591	Snake Meadow Hill, Westford, Middlesex Co., Massachusetts, USA	USGS-U-Th-Pb	USGS-U-Th-Pb
  USGS-U-Th-Pb-01362_207_206	391	385	Zircon			220591	Snake Meadow Hill, Westford, Middlesex Co., Massachusetts, USA	USGS-U-Th-Pb	USGS-U-Th-Pb
  USGS-U-Th-Pb-01362_207_235	364	356	Zircon			220591	Snake Meadow Hill, Westford, Middlesex Co., Massachusetts, USA	USGS-U-Th-Pb	USGS-U-Th-Pb
  USGS-U-Th-Pb-01363_206_238	368	360	Zircon			220591	Snake Meadow Hill, Westford, Middlesex Co., Massachusetts, USA	USGS-U-Th-Pb	USGS-U-Th-Pb
  USGS-U-Th-Pb-01363_207_206	391	385	Zircon			220591	Snake Meadow Hill, Westford, Middlesex Co., Massachusetts, USA	USGS-U-Th-Pb	USGS-U-Th-Pb
  USGS-U-Th-Pb-01363_207_235	371	363	Zircon			220591	Snake Meadow Hill, Westford, Middlesex Co., Massachusetts, USA	USGS-U-Th-Pb	USGS-U-Th-Pb
  USGS-U-Th-Pb-01364_206_238	361	353	Zircon			220591	Snake Meadow Hill, Westford, Middlesex Co., Massachusetts, USA	USGS-U-Th-Pb	USGS-U-Th-Pb
  USGS-U-Th-Pb-01364_207_206	395	387	Zircon			220591	Snake Meadow Hill, Westford, Middlesex Co., Massachusetts, USA	USGS-U-Th-Pb	USGS-U-Th-Pb
  USGS-U-Th-Pb-01364_207_235	366	358	Zircon			220591	Snake Meadow Hill, Westford, Middlesex Co., Massachusetts, USA	USGS-U-Th-Pb	USGS-U-Th-Pb
  USGS-U-Th-Pb-01365_206_238	354	346	Zircon			220591	Snake Meadow Hill, Westford, Middlesex Co., Massachusetts, USA	USGS-U-Th-Pb	USGS-U-Th-Pb
  USGS-U-Th-Pb-01365_207_206	394	386	Zircon			220591	Snake Meadow Hill, Westford, Middlesex Co., Massachusetts, USA	USGS-U-Th-Pb	USGS-U-Th-Pb
  USGS-U-Th-Pb-01365_207_235	360	352	Zircon			220591	Snake Meadow Hill, Westford, Middlesex Co., Massachusetts, USA	USGS-U-Th-Pb	USGS-U-Th-Pb